Fluid door-check



- (No Model.)

, LL-PAGE. FLUID DOOR CHECK.

No. 539,236. Patented May 14, 1895.

NITED ST TES- PATENT O FICE.

ALBERT A. PAGE, OF EAST HAVEN, ASSIGNOR TO THE SARGENT & COM- PANY, OF NEW HAVEN, CONNECTICUT.

FLUID DOOR-CHECK.

SPECIFICATION forming part of Letters Patent No. 539,236,11ated May 14-, 1895.

Application filed November 26, 1894. Serial No. 529,975. (No model.)

To 00% whom it may concern:

Be it known that I, ALBERT A. PAGE, of East Haven, in the county of New Haven and State of Connecticut, have invented a new Improvement in Fluid Door-Checks; and I do hereby declare the following, when taken in connection with the accompanying drawings and the letters of reference marked thereon, to be a full, clear, and exact description of the same, and which said drawings constitute part of this specification, and represent, in

Figure 1, a plan view of one form which 'a door-check constructed in accordance with my invention may assume; Fig. 2, a full-size view in vertical central section on the line a b of Fig. 1; Fig. 3, a view of the casein horizontal section on the line 0 d of Fig. 2, showing the spring removed; Fig. 4, a viewin side elevation of the plunger; Fig. 5, a plan view thereof with its stem in section; Fig. 6, a reverse plan view thereof, showing the platevalve and the twofold function of the screw in securing the valve to the plunger and preventing the latter from rotating on its stem; Fig. 7, a view in transverse section on the line cf of Fig. 4, showing the stem of the plunger; Fig. 8, a detached view'of the spindle, showing its internally-threaded section disconnected from its main upper portion; Fig.

9, a detached view in elevation of the ventvalve.

My invention relates to an improvement in fluid door-cheeks, which are that class of doorchecks in which the restrained or controlled movement of a body of fluid is used to prevent the slamming of the door.

The object of my present invention is to produce a simple, durable device, composed of few parts, and constructed with particular reference to compactness and to making use of the superior effect of a direct thrust of the plunger over a spiral thrust thereof, avail-' able.

With these ends in view, my invention consists in a fluid door-check-having certain details of construction and combinations of parts, as will be hereinafter described, and pointed out in the claims.

In carrying out my invention, as herein shown, I employ a heavy case or cylinder A, adapted in the usual manner to be applied to a door, furnished at. its upper end with a threaded cap A, and formed with an integral closed bottom. The said case is shaped to form within it an annular shoulder A which provides a support for a diaphragm B, which is secured in place by means of screws B,

passing through the edge of the diaphragm, and into the shoulder, the said diaphragm virtually dividing the case into a springchamber C, and a fluid-chamber 'C. chambers have, however, communication with each other through openings b, formed in the diaphragm, for it is to be understood that the fluid, whatever may be employed, is .not strictly confined to circulation in the fluid chamber. Within the said fluid chamber I locate a disleshaped plunger D, having a smooth periphery, which fits closely against the inner walls of the fluid chamber, but not so closely but what the plunger is free to move up and down therein. plunger is rigidly secured to the lower or inner end of a square stem. D, which passes through a squaredopening B formed to receive it in the center of the diaphragm, which holds the stem against rotation without interfering with its longitudinal reciprocation The particular construction of the diaphragm and stem to effect this result, may obviously be greatly varied. Thus the stem may be of any non-cylindrical shape in cross-section, and the opening in the diaphragm shaped to correspond, or, the stem might be made cylindrical and furnished with lugs or wingsplaying in slots leading out of a circular opening formed in the diaphragm to receive the cylindrical part of the stem. Or, the plunger and case might be constructed to prevent the rotation of the former without interfering with the reciprocatory movement thereof. The projecting upper or outer end of the stem has a screw-threaded enlargement or head D but this is not essential, as the threads might be formed'upon the said end of the stem without enlarging the same. As shown, the outer end of the stem terminated within the springchamber, but it may be extended through and projected beyond the same. I

The upper face of the plunger D has a deep annular recess 01, and the plunger is constructed with two oppositely located passages These The said e onvenie t to manuf tu ed 61 leading out of thebottomot] this recess,

ment of the valve toward and away from the lower face of the plunger. As herein shown, this screw has the additional function of securing the plunger against rotation on the lower end of the square stem D, which it does by taking into the stem for a little distance, key-fashion, as illustrated in Fig. 3; The plunger is raised and lowered without spiral movement, by the rotation of the spindle E, which is furnished at its lower end with an internally threaded sleeve-like section F, which receives the threaded head Diforined, at the per ndef he te n Die r 'y h the plunger. As herein shown, this section, is constructed with coupling slots f, receiving coupling-lugs f formed integral with the spindlepro er.

It is not essential that the thread'edseetion F should be made independent of the spin; abut find that e es r e en much th The dld spindle and its coupledsection F, are located within a long. sleeve or bushing G, the lower end of which fits down over ah'ub G', formedj in the center ot the upper face. of the dia; phragm B, while its upper end,which is somewhat reduced in diameter to form, a bearing G fits in an opening formed in the center ot the cap A", The exterior faeeof this sleeve has a longitudinal groove G, show n in Fig. 3, for the reception of the inner end of the door-spring H, the outer end; of which is engagedwith a rib, projecting into the spring chamber C. The projecting upper end of the sleeve is faced to form a nut G which receives and holds against rotation, the notched hub or wheel], the notches of which are taken into by a pawl .L mounted, upon the lower face ot the inner end; of the door-lever K,the

inner end of which fits over the squared outer end of the spindle. The outer endof the said sleeve is connected with a two-part adjustable.casing-lever L, provided atits outer end h e b acke M, dap e he. a e ed e the. door casing. It will be und'erstoodthat e he p unge D is te e p at val op ei r m owe ace y he eetion of gravity, within thelimit ofjmovernent allowedit by the head of the screw E], thus p mitt ng t e fi d't o f eely eegh he p unge e n o the ewen p 't e ef, e fluid-chamber Q.

I y emark h ret t heflh det the eeg nning ef'the p tro t p u ge m y be o at d e t e y hin, the pp r po ti n.

f e flni r h mhe i r p r ion f t. may extend into the spring-chamber, whiehhae free communication with the fluid chamber r h he p e ee b in thediaph aamfit Vhen the plunger begins to movedownward',

which it does at the beginning1of the closing movement of the door, the plate-valve impinges against the fluid in the lower portion of the fluid chamber, and is at once lifted so as to close the passages d d in the plunger,

. whereby the return of the fluid through the 1 said passages iscut off, Just as soon therefore, as the platetvalve is closed, the downward movement of the plunger places the fluid in the lower portion of the fluid chamber under great pressure, so that the fluid resists the described movement of the plunger, and hence the rotation of the spindle which is coupled with the plunger, and hence the closin g movement of the door, which is connected with. the spindle, and can only close as the The resistance same rotates and allows it to. of the confined fluid is now slowly relieved by means of two. vent-passages N and N, the

inner ends of; which respectively open into the lower and upper ends of the fluid chamher, while their outer ends intersect a small valve chamber N formed in a projection N cast integral with the lower portion of the case A, the said valve-chamber receiving a hollow, vent valve 0, open at its outer endfor communication with the passage N,,and containing an opening 0', for communication with the passage N". This valve is held in place in the chamber by means of a retaining nut N, and is furnished at itsprojecting outer endwith anoperating-button N held in place by a small nut N t I It will be readily understood that by rotating the valve by means of its operating buttonN the opening 0 of the valve may be brought into full or partial coincidence with the passageN", which. will thus be virtually contracted, or enlarged so asto offer more or less resistance to the passage of the fluid from the lower to the upper part of the fluidchamber, and' thus give more or less relief to the operation of, the plunger. As herein shown, the edge of the plunger is constructed with a clearance. slot d arranged in alignment with the vent passage Nfl and permitting the free escape of fluid therefrom at the beginning of the downward movement of the plunger.

It is thought it will not be necessary to f urther describe the operation of thedoor check than tosay that when the door is closed, the plunger is located at the bottom of thefluid chamber. Duringthe opening movement of the door, the plunger is lifted directly upward'witho lt rotary movement, theflui d beseli 'ewed. t fle ree y h ough hi asmuch as at this timethe plate-valve is open. At the beginning of the closing movementof the door, the plunger begins to descend, whereupon the plate-valve at once closes, so hat hefiuidint e lower p t f the ch mber s p ace unde gr at pr esu t t n esists the downward movement of the plunger, and the closing of the d0or, which then takes place only as rapidly as the relief passage allows the fluid to work back into the upper portion of thefluidchamber.

ICC

I would call'particular attention to the fact that the pressure of the fluid is exerted downward against the integral bottom of the case, so that no leakage through the case can take place. I

It will also be observed that my improved device secures a direct thrust of the piston which is not rotated, wherebyI secure better results than with apiston which combines reciprocal and rotary movement.

My device is particularly adapted to doorchecks designed to be used with doors opening from right to left, but may be adapted to doors opening the other way by reversing the direction of the screw-threads upon the head D of the sleeve, and within the sleeve-like lower section F of the spindle, that is to say, by replacing the parts mentioned by corresponding parts oppositely threaded.

In view of the changes and modifications suggested, I would have it understood that I do not limit myself to the exact construction shown and described, but hold myself at liberty to make such alterations as fairly fall within the spirit and scope of my invention. Thus, the door-spring and its several connections might be widely varied in construction and arrangement without altering the action of the plunger. If the stern should be extended through the top of the case, it might co-act with anut-likeinstrumentality taking the place of the spindle, and connected with the door-spring, and the door-lever. This construction is thought not to require illustration.

Having fullydescribed my invention, what I claim as new, and desire to secure by Letters Patent, is-

1. In a fluid door-check, the combination with a case containing a fluid chamber, of a diaphragm located in the said case, a nonrotatable plunger located in the fluid chamber in which it moves back and forth, a nonrotatable stem passing through the said diaphragm, rigidly connected at its inner end with the said plunger, and having its projectin g outer end screw-threaded, and a rotatable spindle threaded to coact with the threaded end of the stem, whereby the plunger is moved back and forth, substantially as described.

2. In a fluid door-check, the combination with a case containing a fluid chamber, of a diaphragm located in the said case, a nonrotatable plunger located in the fluid chamber in which it moves back and forth, a stem passing through the said diaphragm, connected at its inner end with the plunger, and having its projecting outer end screw-thread ed, and a rotatable spindle comprising an internally threaded lower section receiving the threaded outer portion of the stem, and rotating with the body of the spindle, substantially as set forth, and whereby the plunger is operated back and forth in the fluid chamber, substantially as described.

3. In a fluid door-check, the combination with a case, of a diaphragm located therein and dividing it into a spring chamber and a fluid chamber, a door spring located in the fluid chamber, a non-rotatable plunger located in the fluid chamber, in which it moves back and forth, a stem rigidly connected at one end with the said plunger and at its other end projecting through the said diaphragm and furnished at its projecting end with screw-threads, and a rotatable spindle entering the spring chamber andfurnished with a removable, internally-threaded, tubular section, receiving the threaded, rojecting end of the stem and interlocked with the body of the spindle for rotation thereby in either direction, substantially as set forth.

4. In a fluid door-check the combination with the case thereof, of a diaphragm located in the said case and dividing the same into spring and fluid chambers, a non-rotatable plunger located in the fluid chamber in which it moves back and forth, a stem passing through the said diaphragm, rigidly connected at its inner end with the said plunger, and having its projecting outer end threaded, a spindle internally threaded to receive the threadedouter end of the stem, a sleeve or tube inserted into-the spring-chamber,resting upon the diaphragm therein, and inclosing and forming a bearing for the spindle, and a door-spring connected at one end with the said tube, and at the other end with the case or cylinder, substantially as described.

In testimony whereof I have signed this specification in the presence of two subscribing witnesses. I

ALBERT A. PAGE. Witnesses:

WILLIAM S. CooKE, CHARLES L. BALDWIN. 

